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Kan Takeda

Publications and source records attributed to Kan Takeda.

At least 55 records · Page 3Linked to original sources
PubMed2003

Lymphatic mapping and sentinel node biopsy during laparoscopic gastrectomy for early cancer.

BACKGROUND/AIMS: Intraoperative lymphatic mapping and sentinel node (SN) biopsy can potentially be combined with minimally invasive surgery, but there are few reports of laparoscopic lymphatic mapping for gastrointestinal cancer. We examined the feasibility and accuracy of laparoscopic lymphatic mapping in predicting lymph node status in patients with gastric cancer. METHODS: Seventeen patients with gastric cancer invading the mucosal or submucosal layers (T1) underwent laparoscopic gastrectomy with lymphatic mapping between March 2001 and May 2002. The day before surgery, a technetium-99m-labelled tin colloid solution was injected endoscopically around the tumor. Immediately after the pneumoperitoneum, patent blue was injected. Gastrectomy was performed in all patients, and blue-stained or radioactive nodes were defined as SNs. Fresh SNs were immediately processed for frozen-section examination by hematoxylin-eosin (H and E) and immunohistochemical (IHC) staining. All non-SNs harvested from resected specimens were subjected to histological examination with H and E. RESULTS: SNs were detected in all patients by combination of the two kinds of tracers. Three patients had lymph node metastases in their final examination, and SNs in these 3 were operatively diagnosed as positive by H and E or IHC staining. Lymphatic mapping and SN biopsy under laparoscopic surgery were performed with 100% accuracy. CONCLUSION: Our preliminary study shows the feasibility of intraoperative lymphatic mapping in laparoscopic gastrectomy for T1 gastric cancer.

Adult↗
PubMed2003

Assessment of fatty acid metabolism in taxan-induced myocardial damage with iodine-123 BMIPP SPECT: comparative study with myocardial perfusion, left ventricular function, and histopathological findings.

UNLABELLED: We investigated myocardial fatty acid metabolism in taxan-induced myocardial damage in patients with advanced lung cancer. PATIENTS AND METHODS: Twenty-five patients with non-small-cell lung cancer were treated with taxan combined with carboplatin intravenously for three cycles. Myocardial SPECT imaging using 99mTc-methoxyisobutyl isonitrile (MIBI) and 123I-15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) was performed successively before and after chemotherapy. Regional uptake scores of BMIPP and MIBI were visually assessed and total uptake scores and the number of abnormal segments were calculated. Left ventricular ejection fraction (LVEF) was obtained by first-pass radionuclide angiocardiography using MIBI. Postmortem pathological examination was performed in 5 patients. RESULTS: Total BMIPP uptake scores after chemotherapy were significantly lower than those before chemotherapy (23.4 +/- 3.4 vs. 26.6 +/- 0.8; p < 0.001). Mean LVEF showed a significant decrease after chemotherapy. Of the 25 patients, 4 exhibited a decrease in LVEF of more than 10%, 1 had a decrease in LVEF to below 50%, and 1 developed congestive heart failure. These 6 patients had significant decreases in total BMIPP uptake scores and increases in the number of abnormal segments as compared with the other 19 patients. Histopathological examination of myocardial tissue showed interstitial edema and disarrayed myocardial cells. CONCLUSION: Taxan impairs myocardial fatty acid metabolism. 123I-BMIPP myocardial SPECT is useful for evaluating the cardiotoxicity induced by taxan.

Adult↗
PubMed2003

Abnormal hyperintensity within the subarachnoid space evaluated by fluid-attenuated inversion-recovery MR imaging: a spectrum of central nervous system diseases.

A variety of central nervous system (CNS) diseases are associated with abnormal hyperintensity within the subarachnoid space (SAS) by fluid-attenuated inversion-recovery (FLAIR) MR imaging. Careful attention to the SAS can provide additional useful information that may not be available with conventional MR sequences. The purpose of this article is to provide a pictorial essay about CNS diseases and FLAIR images with abnormal hyperintensity within the SAS. We present several CNS diseases including subarachnoid hemorrhage, meningitis, leptomeningeal metastases, acute infarction, and severe arterial occlusive diseases such as moya-moya disease. We also review miscellaneous diseases or normal conditions that may exhibit cerebrospinal fluid hyperintensity on FLAIR images. Although the detection of abnormal hyperintensity suggests the underlying CNS diseases and narrows differential diagnoses, FLAIR imaging sometimes presents artifactual hyperintensity within the SAS that can cause the misinterpretation of normal SAS as pathologic conditions; therefore, radiologists should be familiar with such artifactual conditions as well as pathologic conditions shown as hyperintensity by FLAIR images. This knowledge is helpful in establishing the correct diagnosis.

Adult↗
PubMed2003

Stent-graft detachment from aortic wall after stent-graft repair of acute aortic dissection.

Preliminary studies have demonstrated that stent-graft repair is an attractive method for treatment of aortic dissection. However, few reports have described long-term results. A 72-year-old woman with acute type B aortic dissection underwent stent-graft repair. The entry was closed, and the false lumen disappeared completely. The postoperative course was uneventful for 4 years 5 months, when detachment of the stent graft from the aortic wall was noted. Because the device appears to be stable, follow-up is on an outpatient basis.

Aged↗
PubMed2003

Acute and contained rupture of the descending thoracic aorta: treatment with endovascular stent grafts.

PURPOSE: The purpose of this study was to evaluate feasibility and safety of endovascular stent grafting for the treatment of patients with rupture of the descending thoracic aorta. METHODS: Thirteen patients with rupture of the descending thoracic aorta were treated with endovascular stent grafting. Six patients were treated on the day of diagnosis because their vital signs were unstable, and the other seven patients were treated electively. Five patients had infection or potential infection, and the other eight patients did not. Expanded polytetrafluoroethylene-covered or polyester-covered Z stents were used in all patients. RESULTS: Stent grafts were successfully placed in all patients. No endoleaks were observed at the end of the procedure. However, rebleeding was observed within 2 weeks of the procedure in two patients with infection. Six patients (46%) died within 5 months of the procedure (mean survival period, 61 +/- 60 days). All five patients with infection (100%) died, and only one of eight patients without infection (13%) died (P <.01). The remaining seven patients are alive during the mean follow-up period of 21 months (overall survival rate, 54%), although additional surgical interventions, including surgical conversion in one case and upper extremity extraanatomic bypass in the other, were necessary in two of these patients. CONCLUSION: Endovascular stent grafting may be a safe and feasible method for the treatment of rupture of the descending thoracic aorta in selected patients without infection. However, its usefulness in terms of long-term prognosis appears to be extremely limited, especially in patients with infection.

Acute Disease↗
PubMed2003

Evaluation of left ventricular volumes and ejection fraction using fast steady-state cine MR imaging: comparison with left ventricular angiography.

Previous studies demonstrated that magnetic resonance (MR) imaging consistently underestimated angiographic measurements of left ventricular (LV) volumes. The purpose of this study was to determine whether MR imaging with steady-state free precession acquisition (SSFP) can provide improved accuracy and reproducibility in measuring cardiac function in comparison with fast spoiled gradient echo cine MR imaging (SPGR). Twenty patients with cardiovascular diseases who underwent breath-hold cine MR imaging within one week of LV angiography were studied. Two sets of breath-hold cine MR images were obtained, one with SSFP and another with SPGR. The LV volumes determined by two breath-hold cine MR sequences were compared with the results by LV angiography. SPGR cine MR imaging consistently underestimated angiographic LV volumes. The mean difference of LV end-diastolic volume was -22.5 +/- 14.8 ml (p < 0.001) for short-axis planes and -27.7 +/- 21.5 ml (p < 0.001) for long-axis planes. In contrast, LV volumes measured by the SSFP imaging showed a good agreement with the results by angiography. The mean difference of LV end-diastolic volume was -2.5 +/- 14.3 ml (p = N.S.) for short-axis planes and -10.9 +/- 15.1 ml (p < 0.01) for long-axis planes. Standard error of the estimation in measuring LV end-diastolic volume with the SSFP imaging was 3.9% for short-axis images and 4.9% for long-axis images. These values were 7.2% and 8.7% with the SPGR imaging. In conclusion, the SSFP acquisition can provide accurate and noninvasive assessments of LV volumes and ejection fraction within a reduced imaging time.

Adult↗
PubMed2003

Prediction of regional functional recovery after acute myocardial infarction with low dose dobutamine stress cine MR imaging and contrast enhanced MR imaging.

PURPOSE: Previous studies demonstrated that low-dose dobutamine stress cine magnetic resonance imaging (MRI) and delayed contrast-enhanced MRI can provide assessments of myocardial viability. The purpose of this study was to evaluate the comparative diagnostic values of dobutamine cine MRI and delayed contrast-enhanced MRI for predicting functional recovery of myocardial contraction in patients with acute reperfused myocardial infarction. METHODS: Twenty-three patients with myocardial infarction after percutaneous coronary interventions were studied. All patients underwent steady-state cine MRI covering the entire left ventricle at rest and during low-dose dobutamine stress (10 micrograms/kg/min). Delayed contrast-enhanced MR images were acquired to determine transmural extent of hyperenhancement. Second cine MR images in the resting state were obtained 3 to 11 months after revascularization. RESULTS: On the first cine MR images in the resting state, 278 (20%) of 1380 segments demonstrated abnormal, regional contraction (systolic wall thickening < 40%). Of the 175 segments showing functional recovery on the following cine MRI, 156 (89%) segments were recognized as reversible by dobutamine cine MRI and 146 (83%) segments by delayed contrast-enhanced MRI. The sensitivity, specificity, and accuracy of dobutamine stress cine MRI was 89%, 80%, and 86%, respectively. These values of contrast-enhanced MRI were 83%, 72%, and 79%, respectively. The area under the receiver operating curve (ROC) was 0.87 by dobutamine cine MRI and 0.78 by delayed contrast-enhanced MRI (p < 0.05). CONCLUSIONS: The current results using quantitative segmental analysis indicated that low-dose dobutamine stress cine MRI can predict recovery of myocardial contractility with significantly higher diagnostic performance in comparison with contrast-enhanced MRI in patients with myocardial infarction who underwent revascularization.

Adult↗
PubMed2003

Improvement of regional cerebral blood flow after treatment with branched-chain amino acid solutions in patients with cirrhosis.

OBJECTIVE: The administration of solutions rich in branched-chain amino acids leads to mental recovery from acute hepatic encephalopathy in patients with liver cirrhosis. However, the mechanism of action of branched-chain amino acids remains unclear. The purpose of this study was to evaluate the effect of intravenous infusion of branched-chain amino acids on brain perfusion in patients with liver cirrhosis. METHODS: Single photon emission computed tomography scans were performed in 14 patients with liver cirrhosis before and after the administration of branched-chain amino acids in a single-day split-dose protocol. The per cent change in regional brain perfusion was calculated in high frontal, parietal, temporal, occipital lobes and cerebellum. Thereafter, statistical parametric mapping was performed to identify brain regions with abnormal cerebral perfusion. RESULTS: Intravenous infusion of solutions enriched with branched-chain amino acids induced a 13-20% increase in regional cerebral blood flow. Cirrhotic patients had regions of significant hypoperfusion, as determined by statistical parametric mapping, in the left superior parietal and posterior cingulate as compared to the control group. This hypoperfusion of parietal and cingulate regions was not detected after treatment with solutions of branched-chain amino acids. CONCLUSIONS: The results of the present study suggest that administration of solutions enriched with branched-chain amino acids improves cerebral perfusion in patients with cirrhosis.

Aged↗
PubMed2003

Increased myocardial uptake of iodine-123 metaiodobenzylguanidine on delayed images, compared with early images, in patients with multiple system atrophy.

We present 2 interesting cases of multiple system atrophy in which increased myocardial iodine-123 metaiodobenzylguanidine uptake was observed on delayed images (3 hours after injection) compared with early images (15 minutes after injection). These findings have not been previously described. The duration of symptoms was less than 1 year in both these patients. The mechanism responsible for these findings is not clearly understood, but could be related to the pathophysiological changes in the early stage of multiple systemic atrophy.

3-Iodobenzylguanidine↗
PubMed2003

Radiofrequency ablation with and without balloon occlusion of the renal artery: an experimental study in porcine kidneys.

PURPOSE: To compare thermal lesion volumes and associated renal damage (other than thermal lesions) when radiofrequency (RF) ablation is performed with and without balloon occlusion of the renal artery in normal porcine kidneys. MATERIALS AND METHODS: RF ablation was performed in six pigs. An electrode with eight circumferential prongs arranged in a circle 20 mm in diameter was inserted into the lower pole of the kidney. In each animal, renal ablation was performed with balloon occlusion of the renal artery in one kidney and without balloon occlusion in the contralateral kidney. The volume of the thermal lesion and associated renal damage other than the thermal lesion were compared by angiography and histology between the groups of kidneys ablated with and without arterial occlusion. The volume of thermal lesion was measured by tracing the thermal lesions of sliced kidneys and multiplying each area by the slice thickness (5 mm). RESULTS: Renal ablation with arterial occlusion consistently created nearly spherical thermal lesions with a mean volume of 5,399 mm(3) +/- 902. RF ablation without arterial occlusion, conversely, created irregular, mushroom-shaped thermal lesions limited to the region around the prongs and shaft of the electrode, with a mean volume of 2,759 mm(3) +/- 1,069 (P <.001). Renal arteriography showed occlusion of interlobar arteries penetrating the thermal lesions and perfusion defects peripheral to the thermal lesions immediately after RF ablation. Perfusion defects were larger in kidneys ablated with arterial occlusion than in those ablated without arterial occlusion (1,499 cm(2) +/- 354 vs 499 cm(2) +/- 352; P <.001). CONCLUSIONS: Renal RF ablation with arterial occlusion consistently provides larger thermal lesions than ablation without arterial occlusion does, but it induces renal infarction peripheral to the thermal lesion.

Angiography↗
PubMed2003

Metallic stent placement in the pancreatic duct: an experimental study in the normal dog pancreas.

PURPOSE: To evaluate radiologic and histologic changes in the pancreatic duct and parenchyma after placement of metallic stents in normal dog pancreatic ducts. MATERIALS AND METHODS: Eight dogs underwent duodenotomy and placement of a balloon-expandable metallic stent 1.5 mm in diameter and 1 cm in length in the main pancreatic duct. Two dogs each were killed at 1 day and 1, 3, and 5 months after stent placement. Pancreatic duct injection images were obtained before and immediately after stent placement and just before and after sacrifice. Macroscopic and microscopic examinations were also performed. RESULTS: Pancreatic duct injection images revealed mild dilation of pancreatic ducts related to the procedure immediately and 1 day after stent placement. Microscopically, denudation of the ductal epithelium and small foci of fat necrosis were observed. At 1 month or later, ductal stricture (n = 4) and occlusion (n = 2) were found at the downstream edge of the initially stent-implanted region associated with dilation of the duct upstream. Epithelial hyperplasia was observed at the sites of ductal stricture and occlusion at 1 and 3 months. Stents remained in the region in which they were initially placed until 1 month. However, stents had moved downstream from their initial positions at 3 and 5 months. One stent had migrated into the duodenum at 5 months. Stone formation was found in the ductal lumen and around the stents at 3 and 5 months. Ducts and parenchyma became fibrotic proportional to the period of stent implantation. CONCLUSION: Metallic stent placement in the pancreatic duct causes ductal and parenchymal damage related to the procedure and reaction to the stent in the normal dog pancreas.

Animals↗
PubMed2003

Percutaneous radiofrequency ablation of liver neoplasms adjacent to the gastrointestinal tract after balloon catheter interposition.

A hepatocellular carcinoma compressing the duodenum and a metastatic liver tumor adherent to the stomach were treated by radiofrequency ablation after a balloon was percutaneously placed between the tumor and the gastrointestinal tract to avoid bowel perforation. Neither tumor showed enhancement on dynamic contrast material-enhanced CT after radiofrequency ablation. There were no complications related to the procedures.

Aged↗
PubMed2003

Acute myocardial infarction: myocardial viability assessment in patients early thereafter comparison of contrast-enhanced MR imaging with resting (201)Tl SPECT. Single photon emission computed tomography.

PURPOSE: To compare contrast material-enhanced magnetic resonance (MR) imaging with resting thallium 201 ((201)Tl) single photon emission computed tomography (SPECT) for predicting myocardial viability in patients early after acute myocardial infarction. MATERIALS AND METHODS: Inversion-recovery contrast-enhanced MR images and resting (201)Tl SPECT images were obtained in 22 patients after acute myocardial infarction. The (201)Tl SPECT images were obtained 4.3 days +/- 0.2 (standard error) after the onset of myocardial infarction. Contrast-enhanced MR imaging was performed 7.9 days +/- 1.6 after (201)Tl SPECT. Transmural extent of hyperenhancement on contrast-enhanced MR images and regional (201)Tl activity were quantitatively analyzed with a 12-segment model. Regional wall thickening on follow-up cine MR images obtained 67 days +/- 17 after contrast-enhanced MR imaging was used as an index for myocardial viability. Statistical analyses were performed with the chi(2) and two-tailed Student t tests. RESULTS: Both contrast-enhanced MR and resting (201)Tl SPECT images showed significant correlations with regional wall thickening on follow-up cine MR images. The sensitivity, specificity, and accuracy of contrast-enhanced MR imaging in the prediction of viable myocardium were significantly higher than those of resting (201)Tl SPECT (98.0% vs 90.3%, P <.01; 75.0% vs 54.4%, P <.05; and 92.0% vs 81.1%, P <.001, respectively). CONCLUSION: Delayed contrast-enhanced MR imaging can help predict myocardial viability as seen on follow-up cine MR images after acute myocardial infarction, with significantly improved sensitivity, specificity, and accuracy in comparison with those of resting (201)Tl SPECT.

Female↗
PubMed2003

Quantitative assessment of diffusion abnormalities in benign and malignant vertebral compression fractures by line scan diffusion-weighted imaging.

OBJECTIVE: Acute vertebral collapse is common, and it is sometimes difficult to determine whether the cause is benign or malignant. Recently, diffusion-weighted imaging has been reported to be useful for differentiating the two types. The purpose of this study was to evaluate diffusion abnormalities quantitatively in benign and malignant compression fractures using line scan diffusion-weighted imaging. SUBJECTS AND METHODS. Line scan diffusion-weighted imaging was prospectively performed in 17 patients with 20 acute vertebral compression fractures caused by osteoporosis or trauma, in 12 patients with 16 vertebral compression fractures caused by malignant tumors, and in 35 patients with 47 metastatic vertebrae without collapse. Images were obtained at b values of 5 and 1,000 sec/mm(2). The apparent diffusion coefficient (ADC) was measured in vertebral compression fractures and metastatic vertebrae without collapse. RESULTS: The ADC (mean +/- SD) was 1.21 +/- 0.17 x 10(-3) mm(2)/sec in benign compression fractures, 0.92 +/- 0.20 x 10(-3) mm(2)/sec in malignant compression fractures, and 0.83 +/- 0.17 x 10(-3) mm(2)/sec in metastatic vertebral lesions without collapse. The ADC was significantly higher in benign compression fractures than in malignant compression fractures (p < 0.01), although the two types showed considerable overlap. CONCLUSION: Although the quantitative assessment of vertebral diffusion provides additional information concerning compressed vertebrae, the benign and malignant compression fracture ADC values overlap considerably. Therefore, even a quantitative vertebral diffusion assessment may not always permit a clear distinction between benign and malignant compression fractures.

Aged↗
PubMed2003

[Clinical usefulness of reservoir system with a coaxial catheter].

We have developed a new implantable catheter and port system (reservoir) with a 2.9 Fr coaxial catheter. This study was undertaken to evaluate the initial results of the new reservoir system. Fifty-three patients with liver neoplasms underwent implantation of this reservoir owing to tortuousity, angulation, and stenosis of the hepatic arteries, and received repeated arterial infusion chemotherapy. Implantation was technically successful in all patients. Hepatic arterial occlusion occurred at rates of 13.7% at six months and 35.3% at one year. There were no major complications apart from port infection in two patients. This reservoir with a 2.9 Fr catheter expands the indications of hepatic arterial infusion chemotherapy.

Aged↗
PubMed2003

A new prognostic scoring system involving des-gamma-carboxy prothrombin as a useful marker for predicting prognosis in patients with hepatocellular carcinoma.

A staging system for hepatocellular carcinoma was reported from Italy (CLIP). In this study, we evaluate the CLIP scoring system and establish a new scoring system for predicting the prognosis of patients with hepatocellular carcinoma. Patients (n=141) who were diagnosed and who underwent initial treatment at our single institution were recruited retrospectively into this study. We evaluated markers for prognosis, using a stratified Cox proportional hazard regression model and Kaplan-Meier survival analysis. CLIP score differentiated patients with different survival experiences by Kaplan-Meier estimated survival analysis. However, with respect the CLIP score, more than two thirds of patients were included in the early stage (CLIP 0-1), and the group with better prognosis than the survival rate of all patients was the only one with CLIP 0. Multivariate analysis revealed that des-gamma-carboxy prothrombin (DCP) >/=100 mAU/ml (relative risk, 2.06; P=0.0218) was statistically significant as a predictor of poor survival. A new prognostic scoring system included DCP classified patients to 6 well-balanced groups (score 0-5). The new prognostic scoring system 0 group (14.9% of the cohort) and the CLIP score 0 group (34.0% of the cohort) had a median survival of 66.9 and 61.6 months. The new prognostic scoring system performs better for prediction of survival than either the CLIP score or the Child-Pugh stage. In conclusion, the described scoring system provides more accurate prognostic information than the CLIP scoring system. It may help physicians decide more appropriate clinical and therapeutic management.

Aged↗
PubMed2002

Transient splenial lesion of the corpus callosum associated with antiepileptic drugs: evaluation by diffusion-weighted MR imaging.

Transient focal lesions in the splenium of the corpus callosum have been reported in epileptic patients receiving antiepileptic drugs. The characteristic imaging features included an oval high signal lesion on T2-weighted images in the central part of the splenium, no enhancement on post-contrast MR images, and complete reversibility without specific treatment. We report identical MR imaging findings in a depressive patient who had received antiepileptic drugs. In addition, diffusion-weighted MR imaging findings are described in our case, which is the first report on this unique lesion associated with antiepileptic drugs. Although this lesion has been assumed to be vasogenic edema in the previous reports, diffusion-weighted MR imaging showed markedly restricted diffusion of the lesion in the present case, suggesting that cytotoxic edema was the main pathophysiological abnormality.

Adult↗